The formation and retrieval of conditioned fear memories critically depend on the amygdala. Here we identify an inhibitory projection from somatostatin-positive neurons in the central amygdala to parvalbumin-positive neurons in the zona incerta that is required for both recent and remote fear memories. Thus, the amygdala inhibitory input to parvalbumin-positive neurons in the zona incerta, a nucleus not previously implicated in fear memory, is an essential component of the fear memory circuitry.